Implementing UAAG 2.0

1.1.1 Configurable Default Rendering:

The user can specify which types of alternative content to render by default. (Level A)

• Intent of Success Criterion 1.1.1:
  When the author provides alternative content, it is wasted if the user agent doesn't render it for users who need it. Default alternative content is a global option because it is an unreasonable burden for users to change the rendering options every time they visit a new page.
• Examples of Success Criterion 1.1.1:
  • Sally is blind. In the browser's preferences dialog box, Sally specifies that she wants alt text displayed in place of images, and that the document should reflow to allow the entire alt text to be displayed rather than truncated.
  • In the browser's preferences dialog box, Ben chooses to always display the alternative ("fallback") content for embedded objects, such as videos.
  • Brin is deaf. She toggles a menu item which turns on the display of all captions for video and audio content.
• Related Resources for Success Criterion 1.1.1:
  • To be written

1.1.2 Browse and Render:

When a rendered element has alternative content, the user can render alternatives according to the following: (Level A)

• synchronized alternatives for time-based media (e.g. captions, audio descriptions, sign language) can be rendered at the same time as their associated audio tracks and visual tracks, and
• non-synchronized alternatives (e.g. short text alternatives, long descriptions) can be rendered as replacements for the original rendered content.

• Intent of Success Criterion 1.1.2:
  a. There are times when users cannot gain meaningful information from images, charts, graphs, etc. (non-time-based media elements).The author may have provided synchronized alternatives for the media. Users should be able to easily discover the synchronized alternatives provided, and have them render synchronously with the default media.
  
  b. There are times when a user cannot gain meaningful information from a non-time-based media element (images, charts, graphs, etc.). The author may have provided alternatives for this. The user should be able to easily discover the alternatives provided, and have them render in place of the default media.
• Examples of Success Criterion 1.1.2:
  1. Sam is deaf. He is watching a video on a web page. He cannot hear the audio. The author has provided captions for the video. The user agent detecting that captions exist, makes the caption button visible. The caption button toggles the captions on/off.
  2. Sue is blind. She is watching a video on a web page. She cannot see the action on the screen. The author has provided audio-descriptions for the video. The user agent detecting that audio-descriptions exist, makes the AD button visible. The button toggles the audio-descriptions on/off.
  3. Mary has a learning disability. She is reading a page with many images. The images are distracting. Mary is able to turn the images off, and reveal the alternative text (@alt) that the author provided. The alternative text is rendered in place of the images. Mary has the option of having the size of the image remain same or fit the size of the text.
  4. Mary also cannot make sense of the graphs. The author has provided long descriptions for the graphs. Mary toggles the long-description feature. The browser detects the presence of valid @long-descriptions and renders an actionable icon inline after an image. Mary can click on the icon, opening the long-description for that particular graph.
• Related Resources for Success Criterion 1.1.2:
  • See Success Criterion 4.1.2 : Name, Role, State, Value, Description

1.1.3 Identify Presence of Unrendered Alternative Content:

The user can specify that content be rendered with an adjacent indicator when unrendered alternative content is present (e.g. an icon to indicate an image has a short text alternative). (Level A)

• Intent of Success Criterion 1.1.3:
  When the author provides alternative content, it is wasted if users cannot find it. The user agent should make the presence of alternative content evident to the user. Users should not have to hunt and examine every time to see if it includes such content, because such searching can be time-consuming, especially for users whose disability makes input difficult, tiring, or painful. The user should be able to easily identify which items have alternative content, rather than being merely informed that alternative content is somewhere in the view.
• Examples of Success Criterion 1.1.3:
  • Tinan has repetitive strain injuries and seeks to limit scrolling. The user agent renders distinct visual icons in proximity of content that has short text alternatives, long descriptions, and captions. If the icon forces the text to extend beyond a fixed size container the user agent uses global preference settings to determine whether to expand the container, provide scroll bars, or truncate the content.
  • Aosa is blind. When rendering a Web page using synthesized speech, the user agent generates an audible tone to signify the word being read is an acronym, and Aosa can press the * key to hear the expansion. When the phrase being read is the Alt text for an image, another tone indicates that Aosa can press + to hear the longdesc.
  • A button is displayed beneath the playing video to indicate that captions are available and to let the user toggle their display.
• Related Resources for Success Criterion 1.1.3:
  • (Refer to the SC about handling layout/reflow options.)

1.1.4 Rendering Alternative (Enhanced)

: The user can specify the cascade order in which to render alternative content. (Level AA)

• Intent of Success Criterion 1.1.4:
  For a given piece of non-text content the author may have provided one or several alternatives. For example, an image may have different versions based on resolution, ‘alt text’ (@alt) or a link to a long description (@longdesc). A video may have bandwidth alternatives, caption files in different languages, and audio descriptions in different languages. Users can choose which item(s) to render by default, and specify the order of the cascade of alternatives to be rendered if the author did not provide a type of alternative.
• Examples of Success Criterion 1.1.4:
  • Mary has a learning disability. She finds looking at images on a webpage very distracting. Mary would like to see all images rendered in the following order. First, for images with long descriptions have the long description rendered in place of the image. If the long description does not exit, she wants the ‘alt text’ to be rendered. If neither is available, Mary wants the file name rendered. Added functionality would allow Mary to right click (context menu) on an image to list and select the rendering of the available alternatives (thumbnail, original size, full screen, low resolution, high resolution, alt text, long description, file name)
  • Juan is hard of hearing. He wants to always see video on the page. Also, Juan would like the Spanish language track used if available, along with Spanish captions as a default. If these are not available, he wants to see the video with English audio and captions. If no captions are available Juan wants the the video and English audio. Added functionality would allow Juan to right click (context menu) on an video to list and select the rendering of the available alternatives (still image, caption languages, audio languages, audio-description languages)
• Related Resources for Success Criterion 1.1.4:
  • Web Content Accessibility Guidelines (WCAG) 2.0; Guideline 1.1 Text Alternatives and Guideline 1.2 Time-based Media (http://www.w3.org/TR/WCAG20/)

1.2.1 Repair Missing Alternatives:

The user can specify whether or not the user agent should generate and render repair text (e.g. file name) when it recognizes that the author has not provided alternative content. (Level A)

• Intent of Success Criterion 1.2.1:
  When alternative content is missing, it is sometimes useful for users have access to alternative information, such as the filename. Users need to control the flow of this information, because an uncontrolled flow can be distracting and time-consuming. This is particularly important for users with some disabilities, who may not be able to use some forms of content (e.g. images) or may even need to avoid some forms of content (e.g. animations) and therefore choose to replace them with alternative content.
  
  Users need to control the flow of the content when this information is added, because in some cases cases truncating the content to fit its container will make the document unusable (e.g. if important information becomes hidden), while in other cases expanding the container will make the document unusable (e.g. when important cues no longer line up correctly).
• Examples of Success Criterion 1.2.1:
  • Ray is blind and counts on alternative text descriptions for images. There is an image in web content that does not have alternative text provided. The browser displays the string '(image canoe.png)', which includes the file name because that is the only available information about the image.
  • Bintu is deaf and relies on captions to replace audio. A video does not have captions. Bintu selects a caption button, and is informed that no captions exist. The player then analyzes the video soundtrack and provides speech to text translation served as captions. Note: this is an advanced example, not a requirement.
• Related Resources for Success Criterion 1.2.1:
  • Evaluating Web Sites for Accessibility: Overview

1.2.2 Repair Empty Alternatives:

The user can specify whether or not the user agent should generate and render repair text (e.g. file name) when it recognizes that the author has provided empty alternative content. (Level AA)

• Intent of Success Criterion 1.2.2:
  When an author has chosen to code web content for alternative text but not provide any text information (e.g. an empty alt) the user may still need to know any information available about that web content. Some authoring tools may insert empty alternative text by default, even though this is is contrary to accessibility guidelines, and this can prevent users from getting useful information about the element.
• Examples of Success Criterion 1.2.2:
  • A user wanting additional information on an image can right click on an image to get a context menu, then choose properties to get available information about the image without have to find the image in the source code.
  • A photo-sharing web site automatically generates web content with text alternatives. When the photos are initially uploaded, or if the person posting the photos chooses not to caption a photo, an empty text alternative is automatically generated. A person with visual impairments uploads a batch of photos and needs to know which photo is which in order to provide the photo description. The user agent provides a menu option that displays all known information about that file including filename and selected camera info (date, time, size, type, etc.).
• Related Resources for Success Criterion 1.2.2:
  • To be written

1.2.3 Repair Missing Associations:

The user can specify whether or not the user agent should attempt to predict associations from author-specified presentation attributes (i.e. position and appearance). (Level AAA)

• Intent of Success Criterion 1.2.3:
  Users can use the appearance or position of an item to determine its importance when scanning a document for information. Assistive Technologies mostly rely on structured text, such as text coded as heading or labels. If the browser uses heuristics to identify text that stands out from others, it can render the page with the best guess of what the structure could be.
  
• Examples of Success Criterion 1.2.3
  • Saidah uses a web-based text to speech app to read web pages when away from her home computer. She tries to find a news article on a multi-car accident on the freeway she overheard people talking about on the way to library. She goes to a news website to look for an article on the event. The website has no headings on the list of current events articles but has a long list. Saidah does not want to listen to the teaser for each story, and selects a command in her browser to figure out the headings from the appearance of the page. The browser notes the consistent use of a CSS style for phrases in each paragraph that are bold, in a different color and a larger font size. The browser then redraws the page with those phrases marked as headings. Saidah then uses the feature in her text-to-speech app to read out the headings and quickly finds the article on the car accident.
  • Mateus is using a screenreader to complete a form. The form fields are not labeled so he does not know what should be entered in each field. He selects an option in his browser to render the page with structured text, which guesses that the text to the left of each form field is the label, and re-renders the page with the text structured as a label. Mateus finishes completing the form.
• Related Resources for Success Criterion 1.2.3:
  • To be written

1.2.4 Broken Alternative Content:

The user can be notified when the user agent cannot render alternative content (e.g. when captions are broken).

• Intent of Success Criterion 1.2.4:
  Users who have chosen to have alternative content presented to them greatly appreciate understanding whether a non-working requests is due to a source error, user error, or merely a delay. Users who lack this information may incorrectly conclude that a particular site is not accessible to them, or may waste time either waiting for content or attempting to find a non-existent problem in their browser or configuration. Note that it is generally recommended that this type of notification NOT require user response, so as not to interrupt the user's experience.
• Examples of Success Criterion 1.2.4
  • _____ has images turned off and replaced by their alt text. When alt text is missing, an error icon is presented in its place.
  • _____ is watching videos embedded in a Web page. The browser enables a Captions button when it detects that a caption stream is available. The user clicks this to turn on display of captions, but the browser finds the caption stream is invalid. Instead of merely showing blank space, it displays a small message or icon in the caption area to inform the user that the requested captions cannot be displayed.
• Related Resources for Success Criterion 1.2.4:
  • Success criterion 1.1.3 requires that the user be informed when the document indicates that alternative content is present, but the browser may not know that the alternative content is broken until the user actually attempts to render or play it.

1.3.1 Highlighted Items:

The user can globally specify that the following be highlighted so that each class is uniquely distinguished. It is not the intention that all recognized enabled elements be uniquely distinguished, just that they be distinguished from disabled elements. (Level A)

1. selection
2. active keyboard focus (indicated by focus cursors and/or text cursors)
3. active window
4. active viewport
5. recognized enabled elements
6. presence of alternative content
7. recently visited links

• Intent of Success Criterion 1.3.1:
  Users need to be able to easily discover what web content they can interact with. Users with low vision need to be able to highlight selection, content focus, enabled elements and links (including recently visited links) in order to successfully discover and interact with the web content.
  
  Note: In addition to these required categories, it is recommended that user agents also allow the user to highlight the active viewport, even when it is a frame or similar within the active window, which makes it much easier for the user to visually locate the active focus.
  
  Note: Platform conventions will dictate whether or not an inactive keyboard focus (keyboard focus in an inactive viewport) is visually indicated by an inactive cursor.
  
  Note: the definition of visited and unvisited links is up to the user agent. In some cases it might be links visited during the current session, or in other cases links visited in the browser's history until that is cleared.
• Examples of Success Criterion 1.3.1:
  • A web site uses styles to override visited link color. A low vision user wants to know what links have yet to be explored. The user agent provides a dialog box for setting overrides to author-selected link colors.
  • An author has created a web site with CSS styles that removes the content focus outline. The user agent provides a dialog box for setting overrides to authors CSS focus outline declaration.
• Related Resources for Success Criterion 1.3.1:
  • UAAG 1.3.2 Highlighting Options, describes user options to configuring how these categories are highlighted
  • UAAG 2.1.? Keyboard Focus requires every window have an active or inactive keyboard focus at all times

1.3.2 Highlighting Options:

When highlighting classes specified by 1.3.1 Highlighted Itemsand 1.3.3 Highlighted Input Controls, The user can specify highlighting options that include at least: (Level A)

• (a) foreground colors,
• (b) background colors, and
• (c) border (configurable color, style, and thickness)

• Intent of Success Criterion 1.3.2:
  A low vision user needs control over what visual properties work best for highlighting. These include foreground colors, background colors, and visual borders (with the same configurable range as the operating environment's conventional selection utilities)
• Examples of Success Criterion 1.3.2:
  • A low vision wants to know where the text boxes are on a web form. The user wants to set a thick black border around all text boxes. The user agent provides a dialog box allowing the user to override any author settings.
  • Alex has low vision and sometimes has difficulty distinguishing the fields on web forms. He chooses to have all form fields displayed with a yellow background and outlined with a thick black border.
• Related Resources for Success Criterion 1.3.2:
  • CSS 2 specification

1.3.3 Highlighted Input Controls:

The user can have the following highlighted when they are recognized: (Level AA)

• (a) enabled controls that take input (e.g. push buttons, radio buttons, check boxes, and text input fields, but not groupings or static text and images) regardless of whether they are read-write or read-only, and
• (b) elements with scripted input handlers (e.g. images or text ranges that have onClick or onKeyPress events) regardless of whether the current state allows them to operate.

• Intent of Success Criterion 1.3.3:
  When a user looks at a page they often want to quickly find the control they need to accomplish their task, yet in some pages the controls may be "buried" amid a large amount of other content, or may be styled to make it very hard to distinguish from other content. This can be particularly difficult for people with visual impairments, who may not be able to easily distinguish visual differences that may be subtle or obvious to users with average vision. It can also be a problem for people with some cognitive impairments, who may have difficulty distinguishing between items with similar or non-standard appearance. The ability to have these items visually distinguished can greatly help reduce the amount of time or number of commands they need to use examining a page. This success criterion works in conjunction with 1.3.1 Highlighted Items, which ensures highlighting of several other classes of information, and with 1.3.2 Highlighting Options, which ensures that the user can customize the highlighting to meet their visual or cognitive needs.
• Examples of Success Criterion 1.3.3:
  • Binh gets easily frustrated when he cannot locate the buttons and links on a page, usually because they don't have the standard appearance he's used to. By turning on the option to have all links appear in bright purple, and all push buttons and the like drawn with a bright purple border, he can easily scan the page and find the items he's looking for.
• Related Resources for Success Criterion 1.3.3:
  • 1.1.3 Identify Presence of Alternative Content (Level A) requires items with alternative content to be highlighted.
  • 1.3.1 Highlighted Items (Level A) requires highlighting of additional classes, including the selection, the active keyboard focus, and visited and unvisited links.
  • 1.3.2 Highlighting Options (Level A) requires the user be able to customize the appearances of these highlights.

1.4.1 Configure Text:

The user can globally set the following characteristics of visually rendered text content, overriding any specified by the author or user agent defaults: (Level A)

• (a) text scale (i.e. the general size of text) ,
• (b) font family, and
• (c) text color (i.e. foreground and background).

• Intent of Success Criterion 1.4.1:
  Users need to able to access a wide range of font sizes, styles, colors, and other attributes in order to find the combination that works best for their particular needs. For example, some users want to increase font size to make text more legible, while other users want to reduce the font size to decrease the need to scroll the content. In providing these preferences, it is important to avoid making assumptions. For example, some users want to reduce the font size to decrease the need to scroll the content.
• Examples of Success Criterion 1.4.1:
  • Lee has low vision from albinism and has difficulty with screen resolution and brightness. She chooses to have all text displayed in Palatino font, with white text on a black background, and at least 16 points tall. The serif Palatino font has character spacing that resolves better for her vision, while the white on black reduces glare and the larger size allows her to distinguish fine detail more clearly.
  • Tomas has extremely low vision and chooses to have his browser display all text the same size, and sets that size as large as he can without making the letters too tall for his screen. He chooses not to have headings be proportionately larger than normal text because that would make them taller than his screen and so unreadable.
  • Browser A supports only 3 font sizes: Small, Medium, and Large. Lee, who has low vision, needs to use a font size of 16 pt, which is between the medium and large sizes. Browser A provides an option to override the 3 font sizes with the operating system font range, so that Lee can select the 16 pt font size she needs.
• Related Resources for Success Criterion 1.4.1:
  • To be written

1.4.2 Preserving Size Distinctions:

The user can specify whether or not distinctions in the size of rendered text are preserved when that text is rescaled (e.g. headers continue to be larger than body text). (Level A)

• Intent of Success Criterion 1.4.2:
  The relative size of text provides visual cues that help in understanding and navigating web content and because some content may be authored in a way that would make it difficult or impossible to understand when if font distinctions were hidden. For example, headlines in a larger font than the body text. Users who set preferences to enlarge or reduce the text size need to have these visual cues preserved.
• Examples of Success Criterion 1.4.2: Lee finds text easiest to read at 16 pt Palatino, but can chooses to have her browser display all in the Palatino font and at least 16 pt in size. She needs the headlines to scale proportionally (e.g. 24 pt) in order to preserve headline prominence.
• Related Resources for Success Criterion 1.4.2:
  • To be written

1.5.1 Global Volume:

The user can independently adjust the volume of all audio tracks, relative to the global volume level set through operating environment mechanisms. However, the user agent may only override a global mute on explicit user request and if the user has been cautioned about the implication. (Level A)

• Intent of Success Criterion 1.5.1:
  User agents can render audio tracks from a variety sources, and in some cases, multiple audio tracks may be present on a single page. Users should be able to globally set the volume of audio tracks, rather than having to adjust the volume of each audio track being played.
• Examples of Success Criterion 1.5.1:
  • An operating system provides a master audio volume control that applies to all audio tracks rendered within the environment, including the user agent. The user may define a default volume level through a preferences dialog that is retained across sessions.
  • A user encounters a page with two advertisements and one video which begins playback on page load complete. A global mute command, supported via a mute key on the user's keyboard, allows the user to immediately silence the playing audio tracks.
• Related Resources for Success Criterion 1.5.1:
  • To be written

1.6.1 Speech Rate and Volume:

If synthesized speech is produced, the user can specify the following: (Level A)

• speech rate and
• speech volume (independently of other sources of audio).

1.6.2 Speech Pitch and Range:

The user can specify the following for synthesized speech: (Level AA) :

• (a) pitch ("pitch" refers to the average frequency of the speaking voice), and
• (b) pitch range ("pitch range" specifies a variation in average frequency),

1.6.3 Advanced Speech Characteristics:

The user can specify all of the speech characteristics offered by the speech synthesizer. (Level AAA)

• Intent of Success Criterion 1.6.1, 1.6.2, 1.6.3:
  The objective of these success criteria is to allow the user to customize the specified speech characteristics to settings that allow the user to perceive and understand the audio information.
  
  Users may need to increase the volume to a level within their range of perception for example. Users may also wish to increase the rate of synthesized speech presentation because they can understand it at a rate faster than the default setting of the user agent.
  
  Success criterion 1.6.1 covers the characteristics that users most commonly need to adjust and that are adjustable in most technologies, while success criterion 1.6.2 covers characteristics that are less widely altered and less widely supported.
• Examples of Success Criterion 1.6.1, 1.6.2, 1.6.3:
  • A telephone-based web browser starts reading back a web page. The user can press a key to increase the rate at which the information is read back. Similarly, the user may be using this telephone browser in a noisy environment such as a crowded subway. With a key press the user can quickly increase the volume of the speech being heard.
  • Randy has a hearing disability where speech at lower pitches is difficult to hear. He is using an audio browser that reads web pages back to him. He issues a voice command saying "raise pitch" and the overall pitch of the synthetic speech is increased.
• Related Resources for Success Criterion 1.6.1, 1.6.2, 1.6.3:
  • To be written

1.6.4 Synthesized Speech Features:

For synthesized speech, the following features are provided: (Level AA)

• (a) user-defined extensions to the synthesized speech dictionary,
• (b) "spell-out", where text is spelled one character at a time, or according to language-dependent pronunciation rules,
• (c) at least two ways of speaking numerals: one where numerals are spoken as individual digits and punctuation (e.g. "one two zero three point five" for 1203.5 or "one comma two zero three point five" for 1,203.5), and one where full numbers are spoken (e.g. "one thousand, two hundred and three point five").
• (d) at least two ways of speaking punctuation: one where punctuation is spoken literally, and one where punctuation is rendered as natural pauses.

• Intent of Success Criterion 1.6.4:
  The synthetic speech presentation of text can be difficult to understand at times. Success criteria here are aimed at giving the user the ability to adjust the way in which the speech synthesizer presents text to improve understandability.
  
• Examples of Success Criterion 1.6.4:
  • Penny is using a browser that reads web pages to her and reviewing her most recent banking transactions. She has configured a setting in the speech configuration for the browser to have currency spoken as currency instead of digits. She hears a transaction read as "Deposit, two hundred fifty five dollars," as a result of this change.
  • The speech synthesizer incorrectly pronounces technical terms employed in the Georges organization. These terms are consistently mispronounced in a way that makes it difficult for the George to distinguish them, even though they are instantly distinguishable when displayed as text.. A dictionary allows the user to enter a spelling of the name that produces the correct pronunciation from the synthetic speech.
  • A speech synthesizer is repeating a phone number. Penny wishes to easily copy this number so switches to a mode where each digit is spoken as a unique word e.g. five, five, five and so on.
• Related Resources for Success Criterion 1.6.4:
  • To be written

1.7.1 Author Style Sheets:

: The user can turn off the use of author style sheets, and for every author style sheet defined the user can choose whether or not it should be applied to: (Level A)

• (a) the current page, or
• (b) all pages for which it is defined.

1.7.2 User Style Sheets:

The user can turn off the use of user style sheets, and for every user style sheet defined the user can choose whether or not it should be applied to: (Level A)

• (a) the current page, or
• (b) all pages on specified web sites, or
• (c) all pages.

• Intent of Success Criterion 1.7.1 & 1.7.2:
  CSS stylesheets allow for extensive customization of the rendering of web content. Such customization is frequently used to make web content accessible to a wide range of user needs. These success criteria ensure that users of web browsers can fully take advantage of the stylesheets offered by web authors or that the users have created.
• Examples of Success Criterion 1.7.1 & 1.7.2:
  • A user finds yellow text on a black background easiest to read. When a web site is loaded, the user agent provides a menu where the user can select between several stylesheets that the web author has created for the web site. The user selects a stylesheet named yellow on black from a menu in the user agent listing all available stylesheets. The web content is then rendered using this stylesheet.
  • On a shared computer a web site is rendered with black text on a white background that is normally in full color. The user agent provides a menu where the user can de-select a user-defined stylesheet has been applied to the web page and the user easily disables this stylesheet. The web site is now rendered in full color.
• Related Resources for Success Criterion 1.7.1 & 1.7.2:
  • CSS 2 Recommendation: cascade weight rules

1.7.3 Save copies of style sheets:

The user can save copies of the style sheets referenced by the current page, so that they can edit and load them as user style sheets. (Level AA)

• Intent of Success Criterion 1.7.3:
  TBW
• Examples of Success Criterion 1.7.3:
• Related Resources for Success Criterion 1.7.3:

1.8.1 Highlight Viewport:

The viewport with the input focus (including nested viewports and their containers) is highlighted, and the user can customize attributes of the highlighted mechanism, including, but not limited to, shape, size, stroke width, color, and blink rate (if any). (Level A)

• Intent of Success Criterion 1.8.1:
  When a user agent presents content using multiple viewports, users benefit from a clear indication of which viewport has focus. Simply relying upon text foreground and background colors to indicate focus may not provide sufficient, visually perceivable indication for users with low vision. Highlighting of viewport frames using both color, with sufficient contrast, and increase in viewport border thickness can provide multiple visual cues that indicate focus.
• Examples of Success Criterion 1.8.1:
  • A music Web site allows the user to select which of the top 10 songs are available for listening. Each song is presented in a graphical viewport providing a music player. Using a keyboard based screen magnification tool, a low vision user tabs between songs, with the currently selected player viewport highlighted with a thick, yellow border against a dark gray background.
• Related Resources for Success Criterion 1.8.1:
  • To be written

1.8.2 Move Viewport to Selection and Focus:

When a viewport's selection or input focus changes, the viewport's content moves as necessary to ensure that the new selection or input focus location is at least partially in the visible portion of the viewport. (Level A)

• Intent of Success Criterion 1.8.2:
  When content is presented within a viewport and the content extends horizontally or vertically beyond the visible bounds of the viewport, the user must be able to move to a selectable element or elements which may be out of view, and to have the selected content automatically move into view. For keyboard based users and users of screen magnification tools, this allows users an efficient means to view selected content without having to utilize scrolling controls to locate and view the selection.
• Examples of Success Criterion 1.8.2:
  • A screen magnification user is performing a spell check of a blog posting that is contained within a scrollable viewport. The text of the blog posting exceeds the vertical size of the viewport. The blogging software provides a key to move to the first, and then any subsequent, unrecognized words. With two unrecognized words in the posting, the user ignores the first selected word, and presses the keystroke to move to the next which is currently out of view in the last sentence of the posting. As the key is pressed, the viewport scrolls to show the selected word.
  • A user of a screen reader is showing a sighted colleague how to complete a registration form contained within a viewport. The form exceeds the vertical bounds of the viewport, requiring vertical scrolling to view the complete form content. As the screen reader completes each form entry and presses the tab key, the next form control in the tab order scrolls into view if it is not already visible in the viewport.
• Related Resources for Success Criterion 1.8.2:
  • To be written

1.8.3 Resizable:

The user can make graphical viewports resizable, within the limits of the display, overriding any values specified by the author. (Level A)

• Intent of Success Criterion 1.8.3:
  If a graphical viewport contains content that exceeds the dimensions of the viewport, users should have the option to increase the size of the viewport to allow the full image to be displayed without scrolling, within the limits of the physical display screen. This benefits keyboard users who may find it difficult to scroll content and users with cognitive or learning disabilities whose understanding of the content is aided by being able to view the complete image.
• Examples of Success Criterion 1.8.3:
  • A viewport is used to display an image depicting an organization chart. A user with a learning disability has difficulty maintaining a mental representation of the organizational linkages for items out of view. In order to facilitate their understanding of the organization, the user drags the sizing icon on the corners of the viewport to allow the entire chart to be displayed.
• Related Resources for Success Criterion 1.8.3:
  • To be written

1.8.4 Scrollbars:

Graphical viewports include scrollbars if the rendered content (including after user preferences have been applied) extends beyond the viewport dimensions, overriding any values specified by the author. (Level A)

• Intent of Success Criterion 1.8.4:
  When rendered content exceeds the horizontal or vertical bounds of a graphical viewport, scrollbars provide a visible indication that not all of the rendered content is currently visible within the viewport. The scrollbars provide indication to users who may not be able to otherwise recognize that the rendered content is not fully visible.
• Examples of Success Criterion 1.8.4:
  • A Web site presents a recipe within a viewport, and the length of the recipe exceeds the vertical and horizontal dimension of the viewport, though the step by step graphical depiction of the recipe does not make this obvious. A user following the recipe, uses the scroll bar to recognize that additional steps may be present, and scrolls them into view.
• Related Resources for Success Criterion 1.8.4:
  • To be written

1.8.5 Viewport History:

For user agents that implement a viewport history mechanism (e.g. "back" button), the user can return to any state in the viewport history, restoring the prior point of regard, input focus and selection.(Level A)

1.8.6 Open on Request:

The user can specify whether or not top-level viewports (e.g. windows or tabs) open only with an explicit user request or confirmation. (Level A)

1.8.7 Do Not Take Focus:

If new top-level viewports (e.g. windows or tabs) are configured to open without explicit user request, the user can specify whether or not top-level viewports take the active keyboard focus when they open. (Level AA)

• Intent of Success Criteria 1.8.5, 1.8.6 & 1.8.7:
  Unexpected focus and viewport changes can be disorienting for all users, requiring time and effort for the user to orient to the change. These success criteria are intended to allow the user to be in control of when viewport changes happen so the user can orient to the changes in a predictable fashion.
• Examples of Success Criteria 1.8.5, 1.8.6 & 1.8.7:
  • A web page is loaded in the browser that triggers a secondary page (typically known as a pop-up) to open. The user agent presents the user with the initial page requested and an alert that additional content is available. The user can choose to have this pop-up content shown or not, remaining in control of what is displayed in the user agent's viewport. A user agent may also be configured so that pop-ups do open automatically because the user has chosen to automatically have this content available. The user has a setting however to configure pop-ups such that they open in the background. Hence when visiting a web page with this secondary content, focus remains in the primary viewport with the initial page content requested. The user agent alerts the user that secondary content is available in another viewport and the user can activate this viewport on request, perhaps with a click on the notification mechanism.
• Related Resources for Success Criteria 1.8.5, 1.8.6 & 1.8.7:
  • To be written

1.8.9 Close Viewport:

The user can close any top-level viewports (e.g. windows or tabs) . (Level AA)

• Intent of Success Criterion 1.8.9:
  Put the user in control of what viewports the user agent has opened. This reduces distractions from undesired viewports being opened for the user.
• Examples of Success Criterion 1.8.9:
  • Gary is a keyboard-only user who is browsing a web page when a pop-up advertisement suddenly appears in a new window. The advertisement includes a button labelled "Close", but Gary is wary of pressing it since he knows it might install malware. Instead he closes the advertisement with the standard user agent key command for closing windows and tabs.
  • Annabelle has multiple browser tabs open and is finished viewing content in one of them. She activates a close button on that tab to close it.
• Related Resources for Success Criterion 1.8.9:
  • To be written

1.8.10 Same UI:

The user can specify that all top-level viewports (e.g. windows or tabs) follow the current user interface configuration. (Level AA)

• Intent of Success Criterion 1.8.10:
  Users orient themselves to a browsing environment with a variety of techniques. This success criteria is designed to ensure that the user does not have to learn multiple strategies to use the browsing viewport.
• Examples of Success Criterion 1.8.10:
  • Robert uses magnification software. After setting up his user agent, he knows that web content begins predictably one inch from the top of the window, so he can configure his magnification software to present content starting at that location.
  • Courtney has difficulty understanding and using complex user interfaces. She has worked with her sister to set up her browser to have only a few of the most common browser controls displayed and she knows to expect them on every browser window.
• Related Resources for Success Criterion 1.8.10:
  • This is relies on saving and restores settings in 2.7.4

1.8.11 Indicate Viewport Position:

The user can determine the viewport's position relative to the full extent of the rendered content. (Level AA)

• Intent of Success Criterion 1.8.11:
  This criteria targets the ability for a user to easily understand where they are located relative to the total content available for rendering and the amount of content relative to the total being displayed.
• Examples of Success Criterion 1.8.11:
  • A user navigates to a lengthy web page and begins paging through the content. A scroll bar visually indicates the position within the content as the user pages and also that with each paging action only a small portion of the content is being rendered. Another user accesses this web page with a screen reader and has the percentage that the page is scrolled communicated by the screen reader because the user agent makes information from the scroll bar available programmatically.
• Related Resources for Success Criterion 1.8.11:
  • To be written

1.10.1 Text View:

The user can view all text source that is available to the user agent. (Level AA)

• Intent of Success Criterion 1.10.1:
  The source view is the ultimate fallback when the browser cannot properly render some content, or when the user cannot take advantage of the content as rendered or using the mechanisms provided.
• Examples of Success Criterion 1.10.1:
  • When the content author failed to provide alt text or longdesc for an image, the user can, as a last resort, try to get some information by examining the source to see the image's URI, class, and similar attributes.
  • When the user wants to create a customized style sheet for a Web site, they need to identify the style, class, and id attributes it uses.
• Related Resources for Success Criterion 1.10.1:
  • To be written

1.10.2 Outline View:

An "outline" view of rendered content is provided, composed of labels for important structural elements (e.g. heading text, table titles, form titles, and other labels that are part of the content). (Level AA)

Note: The outline constitutes the important structural elements for the user (See 1.10.3). A label is defined by each markup language specification. For example, in HTML, a heading (H1-H6) is a label for the section that follows it, a CAPTION is a label for a table, and the title attribute is a label for its element.

• Intent of Success Criterion 1.10.2:
  Outline views can help all users get a simplified view or overview of a document. They are particularly useful for users with memory or cognitive disabilities, as well as users with serial access to content or who navigate sequentially. The outline view is a type of summary view and should reduce orientation time. A navigable outline view will add further benefits for these users.
• Examples of Success Criterion 1.10.2:
  • A Web browser provides an optional panel displaying a hierarchical list of the headers and tables in the current document. The user is able to expand or shrink portions of the outline view for faster access to important parts of content.
  • A Web browser provides a command to use CSS display and visibility properties to hide all content other than important structural elements such as titles, headings, and table headings.
  • A Web browser provides a structured view of form controls (e.g. those grouped by LEGEND or OPTGROUP in HTML) along with their labels.
  • Amaya table of contents view @@ Editors' Note: Insert photo@@
    This image shows the table of contents view provided by Amaya [AMAYA]. This view is coordinated with the main view so that users may navigate in one viewport and the focus follows in the other. An entry in the table of contents with a target icon means that the heading in the document has an associated anchor.
• Related Resources for Success Criterion 1.10.2:
  • This Success Criterion (1.10.2) deals with making document structure perceivable to the user. It is complimentary to Guideline 4.7 which deals with making document structure navigable.

1.10.3 Configure Elements for Structural Navigation:

The user can configure the set of important elements for the hierarchical view, including by element type (e.g. headers). (Level AAA)

• Intent of Success Criterion 1.10.3:
  Sometimes authors will visually convey relationships between elements by spatially grouping them, by giving them the same coloration or background, and so forth. Users may not be able to perceive those attributes, such as when using a screen reader, or when strong magnification makes it difficult to make a mental model of the screen layout. In those cases the user agent can assist by providing a view of the data that groups elements that that user agent perceives as implying relationships.
• Examples of Success Criterion 1.10.3:
  • Jane uses a mobile device (and is often situationally impaired) and often encounters tables laid out using floating DIV elements with specific class names denoting the visual styling. In this case Jane cannot use the cursor keys to move around these tabular layouts having instead to use the tab key to move sequentially left-to-right top-to-bottom. Jane's browser allows her to configure important elements and so she can pick out the classes associated with thes element, and therefore use the cursor key to move logically through columns or rows.
• Related Resources for Success Criterion 1.10.3:
  • To be written

1.11.1 Access Relationships:

The user can access explicitly-defined relationships based on the user's position in content (e.g. show form control's label, show label's form control, show a cell's table headers). (Level A) :

• Intent of Success Criterion 1.11.1:
  Some users have difficulty perceiving, remembering, or understand the relationships between elements and their contexts. HTML controls and elements are sometimes grouped together to make up a composite control; certain elements relate to others in a recognizable manner, such as relationships with 'id' attributes and child elements. This is the case with Ajax widgets and with form elements. By making sure the user can be informed about these relationships means that, say, visually disabled users can better understand these relationships even if the elements are not adjacent on the screen or the DOM.
• Examples of Success Criterion 1.11.1:
  • John has low vision and uses a screen magnifier to access his Browser. When interacting with tables and spreadsheets John has to move the viewport of the magnifier to understand the row and column titles of the cell with which he is interacting. This takes additional time and effort and is therefore frustrating. John has just purchased a new Browser because it presents the row and column titles when he hovers over a cell - this makes him much more productive at his accounting job.
• Related Resources for Success Criterion 1.11.1:
  • WAI-ARIA
  • UAAG 2.7.3 Location in Hierarchy

1.11.2 Extended Link Information:

The user agent provides for each link: (Level AAA) :

• link title
• technology type (of the linked Web resource)
• internal/external: (whether the link is internal to the resource e.g. the link is to a target in the same Web page)
  

• Intent of Success Criterion 1.11.2:
  Users who use screen readers need to be able to easily discover information about a link, including the title of the link, whether or not that link is a webpage, PDF etc. and whether the link goes to a new page or a different location in the current page, in order to navigate Web content more quickly and easily.
• Examples of Success Criterion 1.11.2:
  • Robert, who uses a screen reader, needs to know whether a given link will automatically open in a new page or a new window. The browser indicates this information so he can discover it before he makes a decision to click on a link.
  • Maria has an attention disorder, new windows opening are a large distraction. She needs to know whether a given link will automatically open in a new page or a new window. The browser indicates this information so she can decide not to follow a link that opens a new window.
• Related Resources for Success Criterion 1.11.2:
  • To be written

2.1.1 Keyboard Operation

: All functionality can be operated via the keyboard using sequential or direct keyboard commands that do not require specific timings for individual keystrokes, except where the underlying function requires input that depends on the path of the user's movement and not just the endpoints (e.g. free hand drawing). This does not forbid and should not discourage providing mouse input or other input methods in addition to keyboard operation. (Level A)

• Intent of Success Criterion 2.1.1:
  A user has many ways to input information into a computer or device, including mouse, keyboard, gesture, and speech. The keyboard paradigm is the most universal interface for text input - even devices that do have a keyboard (like mobile phones) support a software interface for them. A user should be able to navigate, read and use all of the web page or application without needing to use a mouse. Some users do not use a mouse, others can only use a pointing device that uses the keyboard API. Therefore, ensure that the user can interact with enabled components, select content, navigate viewports, configure the user agent, access documentation, install the user agent, and operate user interface controls, all entirely through keyboard input.
  User agents generally support at least three types of keyboard operation:
  • 1. Direct (e.g. keyboard shortcuts such a "F1" to open the help menu; see checkpoint 11.4 for single-key access requirements),
  • 2. Sequential (e.g. navigation through cascading menus), and
  • 3. Spatial (e.g. when the keyboard is used to move the pointing device in two-dimensional visual space to manipulate a bitmap image).
  
  User agents should support direct or sequential keyboard operation for all functionalities. Furthermore, the user agent should satisfy this checkpoint by offering a combination of keyboard-operable user interface controls (e.g. keyboard operable print menus and settings) and direct keyboard shortcuts (e.g. to print the current page).
• Examples of Success Criterion 2.1.1 :
  • The user must be able to do the following through the keyboard alone (or pointing device alone or voice alone):
    • Select content and operate on it. For example, if the user can select rendered text with the mouse and make it the content of a new link by pushing a button, they also need to be able to do so through the keyboard and other supported devices. Other operations include cut, copy, and paste.
    • Set the focus on viewports and on enabled elements.
    • Install, configure, uninstall, and update the user agent software.
    • Use the graphical user interface menus. Some users may wish to use the graphical user interface even if they cannot use or do not wish to use the pointing device.
    • Fill out forms.
    • Access documentation.
  • An author uses the CSS overflow property to constrain the size of a block of content. The user agent provides scroll bars to display text that overflows the container. The user can use the keyboard to enter the element and operate the scrollbars to visually access the content. The user can return to the main flow of the next element on the page (see SC 2.1.3)
  • The author codes a volume control slider widget. The user can focus on the widget, and using the arrow keys to increase or decrease the volume, and then hit another key to move to the next element in the content.
  • Cade has low vision, and can't identify an icon so wants to be able to read its alternative text. Most users would be able to hover the mouse over the icon and have its alternative text displayed as a pop-up ortooltip, but since Cade does not use a mouse, he can activate a command that allows him to use the tab key to move the keyboard focus to elements that have alternative content. Then, when he tabs to the icon, the browser may automatically display the "hover" tooltip, or allow him to press a key to have it displayed.
  • Omar is a speech-recognition user who cannot use his hands to control his computer. It is much easier for him to use keyboard shortcuts then click on an icon in a new program. He needs to be able to see tooltips to discover keyboard shortcuts without having to use the mouse.
• Related Resources for Success Criterion 2.1.1:
  • Microsoft Keyboard accessibility document
  • Apple keyboard
  • Unix

2.1.2 Keyboard Focus (former 1.9.1):

Every viewport has an active or inactive keyboard focus at all times. (Level A)

• Intent of Success Criterion 2.1.2:
  Both the user and some types of assistive technology need to know what will be affected by any keyboard input, so it's important that they be able to tell which window, viewport, and controls have the keyboard focus at any time. This applies whether window and viewport are active (active keyboard focus) or inactive (inactive keyboard focus). Even when a window is inactive, it can be affected by simulated keyboard input sent by assistive technology tools. Active keyboard focus is indicated to the user by focus cursors and text cursors, as required by Guidelines 1.3, and made available to assistive technology, as required by Success Criterion 4.1.6.
• Examples of Success Criterion 2.1.2:
  • Alan launches a web browser and navigates to a web page. Initially the keyboard focus is treated as being on the entire document, and that is exposed to assistive technology, but there is no visible cursor. When he presses the tab key, the focus moves to the first link on the web page, and a cursor in the form of a dotted rectangle appears around that link.
  • Ellen launches a web browser and navigates to a web page that has an enabled edit field. The browser places the keyboard focus on the edit field, so she can immediately start entering text, and it's location is shown using a text cursor (usually a vertical line or i-beam). As Ellen types, the text cursor moves to show where the next character will appear. If she activates another window, the browser may hide the cursor in the now inactive window, but its location is still available to assistive technology.
  • Raymond has low vision. As the keyboard focus moves from one control to another, or one window to another, his screen enlarger utility detects the focus change and pans its viewport to keep the focus location visible.
• Related Resources for Success Criterion 2.1.2:
  • Guideline 1.3 (Provide highlighting for selection, active keyboard focus, enabled elements, visited links) ensures that the focus location is made visible to users.
  • Success Criterion 4.1.6 (Properties) ensures that the focus location is available to assistive technology.

2.1.3 Viewport Navigation (former 1.9.2 & 1.9.4):

The user can move the active keyboard focus to any viewport. (Level A)

• Intent of Success Criterion 2.1.3:
  Each viewport has a keyboard focus (per 2.1.2), but it's also important that the user be able to navigate to that viewport, making its keyboard focus become the active keyboard focus. This navigation can be between viewports within the application, or between windows or applications. This includes the user agent's user interface, extensions to the user interface (e.g. add-on), content, and plug-ins handling content.
• Examples of Success Criterion 2.1.3:
  • Ruth is working in her web browser, where one document window (viewport) is active (has the active keyboard focus). When she switches to her word processor, the web browser's window and its keyboard focus become inactive, and it hides its cursor. When she switches back to the browser window, it reactivates that viewport, its keyboard focus becomes active again, and its cursor reappears in the same location as when she switched to a different application.
  • A developer creates an extension to a user agent that allows the user to add notes about each web page being visited. A user can press a shortcut key to move focus to the user interface of this extension and interact with the functionality offered by the extension. Similarly, the user presses another key to move focus back to the main viewport for the user agent in the same location as when she moved to the plugin.
• Related Resources for Success Criterion 2.1.3:
  • 2.2.1 ensures that the user can navigate to elements within the viewport.

2.1.4 Specify preferred keystrokes: (former 2.1.2)

: The user can override any keyboard shortcut including recognized author supplied shortcuts (e.g. accesskeys) and user interface controls, except for conventional bindings for the operating environment (e.g. arrow keys for navigating within menus). (Level A)

• Intent of Success Criterion 2.1.4:
  Some users may be able to hit certain keys on the keyboard with greater ease than others. Assistive technology software typically has extensive keyboard commands as well. The goal of this SC is to enable the user to be in control of what happens when a given key is pressed and use the keyboard commands that meet his or her needs.
  
• Examples of Success Criterion 2.1.4:
  • Laura types with one hand and finds keys on the left side of the keyboard easier to press. She browses to a web page and notices that the author has assigned access keys using keys from the right side of the keyboard. She opens a dialog in the user agent and reassigns the access keys from the web page to the left side of the keyboard home row.
  • Elaine's screen magnification program uses alt+m to increase the size of the magnified area of the screen. She notices that in her web browser, alt+m is a hotkey for activating a home button that stops her from being able to control her magnification software. She opens a hotkey reassignment feature in the user agent, and sets alt+o to be the new hotkey for the home button. Her screen magnification software now works correctly.
    
• Related Resources for Success Criterion 2.1.4:
  • To be written

2.1.5 No Keyboard Trap (former 2.1.3)

: The user agent prevents keyboard traps as follows: (Level A)

• (a) in the UI: if keyboard focus can be moved to a component using the keyboard, then focus can be moved away from that component using standard sequential keyboard commands (e.g. TAB key)
• (b) in the rendered content: provides a documented direct keyboard command that will always restore keyboard focus to a known location (e.g. the address bar).
• (c) in the rendered content: provides a documented direct keyboard command that will always move keyboard focus to a subsequent focusable element

• Intent of Success Criterion 2.1.5:
  Intent: If the user can put focus on an element, that they can remove focus and move on to the next element. This is often a problem with embedded objects. The user agent needs to provide a way to always return to the previous or next element in the content, or a known location, such as the address bar. The user agent also needs to be able to take control back from the embedded object, no matter what it is.
  
• Examples of Success Criterion 2.1.5:
  1. The user can press tab to put focus on an embedded object and can press shift-tab to move focus to the previous object and tab to move focus to the next object.
  2. The user has moved the focus to a toolbar extension that does not relinquish control back to the user agent. The user can press Alt-D to move focus to the address bar.
  3. The user has moved the focus to an embedded scripted application that was poorly programmed. the user can press alt-N (or any documented key combination) that overrides the scripting and moves the focus to the next element in the content.
• Related Resources for Success Criterion 2.1.5:
  • Compound documents
  • Other SC in UAAG.

2.1.6 Separate Selection from Activation: (former 2.1.4)

The user can specify that selection is separate from activation (e.g. navigating through a set of radio buttons without changing which is the active/selected option). (Level A)

• Intent of Success Criterion 2.1.6:
  This is a repair function for when an author violates WCAG, but the user still needs to be able to read a page without necessarily activating any controls.
  
• Examples of Success Criterion 2.1.6:
  • when a user opens a drop down menu from the keyboard, they must be able to use the arrow keys to move up and down the list, without triggering an action from the items they are moving past.
  • A list of radio buttons where putting the focus on the radio button to read it causes the radio button to be selected. The user should be able to arrow or tab through the list of radio buttons without causing any one to be selected. Selection is a separate discrete operation like spacebar. This overrides any author provided scripting behavior.
    
• Related Resources for Success Criterion 2.1.6:
  • ARIA
  • WCAG

2.1.7 Follow Text Keyboard Conventions (former 2.1.5)

: Views that render text support the standard text area conventions for the operating environment, such as character keys, Backspace/Delete, Insert, arrow key navigation (e.g. caret browsing), Page Up/Page Down, navigate to start/end, navigate by paragraph, shift-to-select mechanism. (Level A)

• Intent of Success Criterion 2.1.7:
  Providing a full set of keyboard inputs allows users to efficiently--or at all--perform necessary tasks. Making these inputs consistent within and across programs greatly reduces learning curve, cognitive load, and errors.
• Examples of Success Criterion 2.1.7:
  • Directional keys, letter keys, and the Enter key function should allow navigation within and activation of drop-down menus.
  • Ctrl+C or Command+C should copy selected text to the clipboard, allowing the user to avoid manually retyping, and possibly needing to memorize, large amounts of data.
    @@ Editors' Note: comment - what happens when things are not consistent. closing dialog boxes are inconsistent ESC or ALT-F4, might be text area keyboard conventions/controls, not just navigation. @@
• Related Resources for Success Criterion 2.1.7:
  • To be written

2.1.8 Make Important Command Functions Efficient (former 2.1.9)

: Important command functions (e.g. related to navigation, display, content, information management) are more efficient than sequential keyboard navigation. (Level AA)

• Intent of Success Criterion 2.1.8 :
  Let the user access commonly used functions as efficiently as possible. Efficient keyboard navigation is especially important for people who cannot easily use a mouse.
• Examples of Success Criterion 2.1.8:
  • The user can open a document by pressing Ctrl+O or Command+O.
  • The user can temporarily enlarge the rendered content by pressing Ctrl+Plus, rather than having to invoke a menu, choose a command to display a dialog box, select a tab, etc.
• Related Resources for Success Criterion 2.1.8:
  • Links to 1.1. Comply with applicable specifications and conventions

2.1.9 Allow Override of User Interface Keyboard Commands (former 2.1.10):

The user can override any keyboard shortcut binding for the user agent user interface except for conventional bindings for the operating environment (e.g. access to help). The rebinding options must include single-key and key-plus-modifier keys if available in the operating environment. (Level AA)

• Intent of Success Criterion 2.1.9:
  The intent of this success criterion is to ensure that people using a keyboard interface have the ability to remap the user agent's keyboard shortcuts in order to avoid keystroke conflicts with assistive technology, reduce number of keystrokes, use familiar keystroke combinations, and optimize keyboard layout (e.g. for one-handed use). This is important for people with dexterity issues where every keystroke can be time consuming, tiring or painful. It is also important for people using assistive technologies such as screen readers, where many keystrokes are already in use by the assistive technology.
• Examples of Success Criterion 2.1.9:
  • Ctrl+f may be a command in a screen reader to read the item with focus and this is also typically a user agent find command. The user agent should allow the user to reassign the find command to a non-conflicting key binding. To allow this level of user control, the user agent could provide a list of user interface features and default keyboard assignments with options for the user to assign new key combinations. User keyboard customizations should be saved similar to other user preferences by the user agent.
  • Jim, a one handed keyboardist, needs to map all keys to the left side of the keyboard in order to quickly and comfortably reach the keyboard shortcuts he uses frequently.
• Related Resources for Success Criterion 2.1.9:
  • To be written

2.4.1 Find:

The user can perform a search within rendered content (e.g. not hidden with a style), including text alternatives, for any sequence of characters from the document character set. (Level A)

• Intent of Success Criterion 2.4.1 :
  To provide a function that allows the user to easily locate desired information in rendered or alternative text. Give the option of searching the alternative content. In the case of an embedded user agent, (e.g. media player), the embedded user agent provides the search for its content. @@ Editors' Note: Is this even necessary? Who does the search in an embedded video player?"@@
• Examples of Success Criterion 2.4.1 :
  • A user wants to locate a text string in a long document. The user agent provides a mechanism for entering the desired text string, such as a text box with a search button.
  • A user wants to search for text in all views of the document, including views of the text source (source view)
  • A user wants to search the element content of form elements (where applicable) and any label text.
  • @@ Editors' Note: searching video captions??@@
  • @@ Editors' Note: Searching embedded SVG?@@
• Related Resources for Success Criterion 2.4.1 :
  • WCAG
  • 2.6.2 ,3,4,5

2.4.2 Find Direction:

The user can search forward or backward from the focused location in content. The user is notified of changes in search direction. The user is notified when the search reaches the upper or lower extent of the content based on the search direction. (Level A)

• Intent of Success Criterion 2.4.2 :
  Searching in any direction from the current point of focus allows for maximum flexibility in allowing the user to easily locate the text used in the search. Users for who reading is difficult can greatly reduce the amount of reading required to find the information needed. Searching improves navigation efficiency which is especially important for people with dexterity issues where every keystroke can be time consuming, tiring or painful. It is recommended that the user also has the ability to search forward or backward within any selected content. @@ Editors' Note: needs some explanation. how to keep searching within the selected content
• Examples of Success Criterion 2.4.2 :
  • A user has been reading through a web page and wants to quickly locate a phrase previously read. When opening the browser's page search feature, the user has options to search forward and backward from the current location. If the search reaches an endpoint in the document, the user is notified that the search has wrapped around, such as with an alert box or other indication.
• Related Resources for Success Criterion 2.4.2 :
  • To be written

2.4.3 Match Found:

When there is a match, the user is alerted and the viewport's content moves so that the matched text content is at least partially within it. The user can search for the next instance of the text from the location of the match. (Level A)

• Intent of Success Criterion 2.4.3 :
  It is important for the user to easily recognize where a search will start from.
  @@ Editors' Note: If the caret has been moved, from its new location.@@
• Examples of Success Criterion 2.4.3 :
  • Example: Jules is low vision and uses a magnified screen. She frequently searches for terms that appear multiple times in a document that contains a lot of repetition. It is important that the viewport moves and if necessary her screen scrolls after each search so she can easily track where she is in the document.
• Related Resources for Success Criterion 2.4.3 :
  • To be written

2.4.4 Alert on No Match:

The user is notified when there is no match or after the last match in content (i.e. prior to starting the search over from the beginning of content). (Level A)

• Intent of Success Criterion 2.4.4 :
  It is important for users to get clear, timely feedback so they don't waste time waiting or, worse, issue a command based on a wrong assumption. It is important during a search that users are informed when there is no match or that the search has reached the beginning of the document.
• Examples of Success Criterion 2.4.4 :
  • Dennis uses a screen reader. As soon as he gets a message that there is no match he goes on to search for something else. If he does not get a message he wastes time retrying the search to make sure there is not a match.
• Related Resources for Success Criterion 2.4.4 :
  • To be written

2.4.5 Advanced Find:

The user agent provides an accessible advanced search facility, with a case-sensitive and case-insensitive search option, and the ability for the user to perform a search within all content (including hidden content and captioning) for text and text alternatives, for any sequence of characters from the document character set. (Level AA)

• Intent of Success Criterion 2.4.5 : Searching is much more useful when the user can specify whether case matters in a search and when the user can search alternative text.
  
  
• Examples of Success Criterion 2.4.5 :
  • Dennis uses a screen reader. He wants to find all the instances of his friend Bill in a blog post about finances. He needs to specify case in order to avoid stopping at instances of "bill". Later, he searches for his friend's name in a blog post about poetry where the author never uses capital letters. In this instance he specifies that case does not matter.
  • Dennis he remembers a portion of a caption for something he had seen before that he wants to find. He needs to be able to search on the caption.
• Related Resources for Success Criterion 2.4.5 :
  • To be written

2.6.1 List event handlers:

The user can, through keyboard input alone, call up a list of input device event handlers explicitly associated with the keyboard focus element. (Level A)

• Intent of Success Criterion 2.6.1 :
  Users interacting with a web browser may be doing so by voice, keyboard, mouse or another input technology or a combination of any of these. No matter how the user is controlling the user agent, he or she need to know all the input methods assigned to a particular piece of content.
• Examples of Success Criterion 2.6.1 :
  • A user may tab to a link that has a flyout menu that appears OnMouseOver. The User agent needs to notify the user of this menu so he or she can know the menu is available. Other success criteria ensure the keyboard user here can interact with this menu.
• Related Resources for Success Criterion 2.6.1:
  • To be written

2.6.2 Activate any event handler:

The user can, through keyboard input alone, activate any input device event handlers explicitly associated with the keyboard focus element. (Level A)

• Intent of Success Criterion 2.6.2 :
  Although it should not do so, some Web content is designed to work only with certain input devices, such as a mouse, and make functionality available only through event handlers for those devices. Some users interacting with a web browser may be doing so by voice, keyboard, mouse or another input technology or a combination of any of these. No matter how the user is controlling the user agent, he or she must be able to activate any of the event handlers regardless of the interaction technology being used.
• Examples of Success Criterion 2.6.2 :
  • A user who cannot use a mouse needs to activate a flyout menu that normally appears OnMouseOver. The user should be able to navigate to a link and activate it using keyboard shortcuts.
• Related Resources for Success Criterion 2.6.2 :
  • To be written

2.6.3 Activate all event handlers:

The user can, through keyboard input alone, simultaneously activate all input device event handlers explicitly associated with the content focus element. (Level A)

• Intent of Success Criterion 2.6.3 :
  One input method should not hold back another. People who don't use a mouse shouldn't necessarily have to map their input methods to the same steps a mouse user would take.
• Examples of Success Criterion 2.6.3 :
  • Speech input users may combine moving the mouse up, left and clicking in a single command phrase.
  • A link has an onmousedown and an onmouseup event link. The keyboard user can use 1 key click to activate both events.
• Related Resources for Success Criterion 2.6.3 :
  • To be written

2.7.1 Change Preference Settings

The user can change settings that impact accessibility. (Level A)

2.7.2 Persistent Accessibility Settings

: User agent accessibility preference settings persist between sessions. (Level A)

2.7.3 Restore all to default:

The user can restore all preference settings to default values. (Level A)

2.7.4 Multiple Sets of Preference Settings:

The user can save and retrieve multiple sets of user agent preference settings. (Level AA)

2.7.5 Restore related preferences to default:

The user can restore groups of related preference settings to default values (e.g. reset keyboard shortcuts, reset colors and sizes of rendered content). (Level AA)

2.7.6 Change preference setting outside the UI:

The user can adjust preference settings from outside the user agent user interface. (Level AA)

2.7.7 Portable Preference Settings:

The user can transfer preference settings across locations onto a compatible system. (Level AAA)

2.7.8 Preferences Wizard:

A wizard helps the user to configure the accessibility-related user agent preferences (at least). (Level AAA)

• Intent of Success Criterion 2.7.8 :
  Users who rely on accessibility settings do so for multiple reasons and may want to adjust software settings in many differing fashions. It is key to allow software settings that impact accessibility to be configured to meet these differing needs. The easier such settings are to discover, the more rapidly the user looking for such settings can tailor the software to suit his or her needs. Saving such configuration changes between browsing sessions allows the software to work the way the user wants each time the application is used.
• Examples of Success Criterion 2.7.8
  • A user who relies on larger text sizes when browsing web pages, locates a text adjustment setting in a browser's menus. The user sets the text size to the size that makes web content readable. .
  • A user locates a control in a web browser called options. Activating this control leads to a series of tabs for adjusting multiple browser settings. One tab is listed as accessibility and has settings such as text size, use custom style sheet, display alternative text in place of images, enable caret browsing and other settings determined to be of benefit to users with disabilities.
  • A user is exploring settings for a web browser and locates an option called accessibility. The user is then guided through a series of questions asking about how he or she prefers to use software. Questions such as color preference, text size, ability to view images, the need for captions on videos and such are asked. When the user completes these questions, appropriate browser options are configured and stored.
  • A user who has configured accessibility settings in a browser needs to use that application in the same browser on another computer. The browser allows the user to transfer such settings from one computer to another, saving the need to reconfigure the second machine.
  • @@ Editors' Note: add another example of persistence@@
• Related Resources for Success Criterion 2.7.8
  • SCORM Editors' Note: (Jutta's work) - find current reference @@

2.8.1 Configure Position:

When graphical user agent user interfaces have toolbars, panels, inspectors, or similar, the user can add, remove and configure the position of user agent user interface controls from a pre-defined set. (Level AAA)

• Intent of Success Criterion 2.8.1 :
  The objective of this criteria is to allow the user to customize the toolbars of a user agent in ways that work best for the method in which he or she is using the browser. This can reduce keystrokes, bring buttons into view that are hidden by default or otherwise allow the user to interact with the user agent in a more efficient fashion. Users with dexterity impairments or mobility impairments may have problems making the large movements required to select between non-adjacent controls which they need to use frequently. Similarly users with low vision may have to excessively move their magnified view-port to see frequently used controls. Enabling these controls to be situated together removes much of the strain faced by these users, and increases productivity as task completion times are decreased.
• Examples of Success Criterion 2.8.1 :
  • Martin accesses the computer by pressing keys with a stick held in his mouth known as a mouthstick and gets around the user agent with taps on the tab and arrow keys. The designers of a user agent have decided to place a button for printing a web page as the last button on a toolbar. This button requires six presses of a right arrow key to reach for Carl and is the only button he uses on the toolbar. Using a preferences dialog, Martin is able to configure this toolbar to only show the Print button, reducing the number of presses he must issue with his mouthstick to one.
• Related Resources for Success Criterion 2.8.1 :
  • WAI-ARIA

2.8.2 Restore Default Toolbars:

The user can restore the default toolbar, panel, or inspector configuration. (Level AAA)

• Intent of Success Criterion 2.8.2 :
  Mistakes happen. If a user has modified the toolbar incorrectly it can often be difficult to return to a stable state so that these errors can be corrected. There are additional pressures in this regard for people with learning difficulties who make more use of toolbars than they do of textual menus. Building an easily selectable mechanism to restore these defaults saves user time and reduces stress.
• Examples of Success Criterion 2.8.2 :
  • Jack is an 80 year old web surfer who is intellectually very sharp but experiences tremors in his hands when required to make fine movements with the mouse. To help himself he is setting up the toolbar so that 'spacers' are placed between each component to prevent accidental selection of adjacent buttons. Today his tremors are particularly bad and Jack makes a number of mistakes becoming increasingly frustrated that while trying to correct these errors he begins to make many more. Jack just wants to start over. Luckily the browser manufacturer has included an easy mechanism to restore the default toolbar configuration. Jack chooses this option and successfully starts over the next day.
• Related Resources for Success Criterion 2.8.2 :
  • WAI-ARIA

2.9.1 Timing Adjustable

: Where time limits for user input are recognized and controllable by the user agent, the user can extend the time limit. (Level A)

• Intent of Success Criterion 2.9.1 :
  Users of assistive technology, such as screen readers, and those who may require more time to read or understand and act upon content (e.g. individuals with reading disabilities or non-native readers of the presented language) should be able to extend or override any content/author imposed presentation / interaction time limits.
• Examples of Success Criterion 2.9.1 :
  • News Alerts: A news organizations Web site has a region of the home page which presents featured stories, cycled every 3 seconds. A user with low vision, using a screen magnifier, requires more than three seconds to read the news item and select it. The user agent provides the user with a global option to freeze all timed events using a keyboard command. Another keyboard command resumes the timed presentation.
  • Session Inactivity Timeouts: A screen reader user is logged into a financial services Web site and is reading the site's detailed privacy policy. Because of security policy, the site will terminate the session of any user who has been inactive for 5 minutes. A prompt will appear warning of the impending log off without further action. This user is able to select an option in her non-visual user agent that automatically responds to those prompts if the user agent is currently reading the content.
• Related Resources for Success Criterion 2.9.1 :
  • To be written

2.10.1 Three Flashes or Below Threshold:

In its default configuration, the user agent does not display any user interface components or recognized content that flashes more than three times in any one-second period, unless the flash is below the general flash and red flash thresholds. (Level A)

• Intent of Success Criterion 2.10.1 :
  The intent of this Success Criterion is to guard against inducing seizures due to photosensitivity, which can occur when there is a rapid series of general flashing, or red flash. A potentially harmful flash occurs when there is a pair of significantly opposing changes in luminance, or irrespective of luminance, a transition to or from a saturated red occurs.
• Examples of Success Criterion 2.10.1 :
  • A single, double, or triple flash -- as long as it does not include changes to or from a saturated red -- may be used to attract a user's attention, or as part of an interface animation.
  • An error condition is indicated by flashing that continues until acknowledged by the user. In order to avoid triggering seizures, the flashing is limited to fewer than three times per second, and, to be extra cautious, it is not red.
• Related Resources for Success Criterion 2.10.1 :
  • ITC Guidance Note for Licensees on Flashing Images and Regular Patterns in Television: http://stakeholders.ofcom.org.uk/binaries/broadcast/guidance/gn_flash.pdf

2.10.2 Three Flashes:

In its default configuration, the user agent does not display any user interface components or recognized content that flashes more than three times in any one-second period (regardless of whether not the flash is below the general flash and red flash thresholds). (Level AAA) [WCAG 2.0]

• Intent of Success Criterion 2.10.2 :
• The intent of this Success Criterion is to guard against inducing seizures due to photosensitivity, which can occur when there is a rapid series of general flashing, or red flash. A potentially harmful flash occurs when there is a pair of significantly opposing changes in luminance, or irrespective of luminance, a transition to or from a saturated red occurs. 2.10.2 has the same effect as 2.10.1, only goes further to ensure that more sensitive users can traverse the Web without potentially harmful effects.
• Examples of Success Criterion 2.10.2 :
  • refer to 2.10.1
• Related Resources for Success Criterion 2.10.2 :
  • refer to 2.11.2 and 2.11.6

@@ Editors' Note: Add SC based on this note from IRC of 10 November 2010: We could consider adding to this section a recommendation that messages have a checkbox that lets the user avoid getting the message again. But I'm not sure how we could write it to have an appropriate scope, that is only apply to messages where it's appropriate. AND when you do have those check boxes, it's also useful to have something in the application's settings that allows the user to reset those to their default, thus making all the messages visible again.@@

3.1.2 Option to Ignore:

The user can turn off rendering of non-essential or low priority text messages or updating/changing information in the content based on priority properties defined by the author or the user agent. (Level AA)

• Intent of Success Criterion 3.1.2 :
  Messages designed to inform the user can be a burden to users for whom keypress is time-consuming, tiring, or painful. It's important that these users be able to avoid unnecessary messages.
• Examples of Success Criterion 3.1.2 :
  • The browser has an update ready. The user should have the option to be informed of an update or, instead, only get update information when the user actively requests it.
  • A web page has a stock market ticker display. A user with cognitive disabilities is distracted by the page flicker and wishes to turn off the update. The browser has an menu option to set the level of interruptions, that the user sets to off. @@ Editors' Note: add this example @@
• Related Resources for Success Criterion 3.1.2 :
  • WAI-ARIA

3.2.1 Form Submission:

The user can specify whether or not recognized form submissions must be confirmed. (Level AA)

• Intent of Success Criterion 3.2.1 :
  Users need to be protected against accidentally submitting a form. Some assistive technologies use the Enter key to advance to the next field. If the form is designed to submit on Enter, the user can unknowingly submit the form. Those users need to be able to disable the ability to submit on Enter.
• Examples of Success Criterion 3.2.1 :
  • Upon installation of a web browser, a screenreader user selects an option to disable form submission on Enter. This is a preference option that can be easily discovered and changed by the user in the future. This allows the user to complete forms from the banking website knowing that the submit button must be selected in order to submit the form.
• Related Resources for Success Criterion 3.2.1 :
  • @@ Editors' Note: link to section 2.1, especially 2.1.2 and 2.1.10 @@

3.3.1 Accessible documentation:

The product documentation is available in a format that meets success criteria of WCAG 2.0 Level "A" or greater. (Level A)

• Intent of Success Criterion 3.3.1 :
  User agents will provide documentation in a format that is accessible. If provided as Web content, it must conform to WCAG 2.0 Level "A" and if not provided as Web content, it must be in conformance to a published accessibility benchmark and identified in any conformance claim for the user agent. This benefits all users who utilize assistive technology or accessible formats.
• Examples of Success Criterion 3.3.1 :
  • A user agent installs user documentation in HTML format conforming to WCAG 2.0 Level "A". This documentation is viewed within the user agent and is accessible in accordance with the conformance of the user agent to UAAG 2.0.
  • A user agent provides documentation in HTML format conforming to WCAG 2.0 Level "AA" and is available online. In addition, the user agent provides user documentation in a locally installed digital talking book content format in conformance with a recognized, published format.
• Related Resources for Success Criterion 3.3.1 :
  • To be written

3.3.2 Document Accessibility Features:

All user agent features that benefit accessibility are documented. (Level A) @@ Editors' Note: write a definition of "benefit accessibility" - as contributing to conforming to these guidelines or a feature specifically added to improve accessibility @@

• Intent of Success Criterion 3.3.2 :
  User agent documentation that includes listings and descriptions of features supporting or benefiting accessibility permits users to have access to a description of accessibility and compatibility features. This benefits all users with disabilities who may require assistance in identifying which accessibility features may be present or how to configure those features to work with assistive technology.
  
  The user should be able to easily discover detailed information about the user agent’s adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, platform standards such as MSAA or JAA, and third-party standards such as ISO 9241-171, and should be able to do so without installing and testing the accessibility features.
• Examples of Success Criterion 3.3.2 :
  • In a section entitled "Browser Features Supporting Accessibility", a vendor provides a detailed description of user agent features which provide accessibility, describing how they function, and listing any supported third party assistive technologies that may be supported or required.
• Related Resources for Success Criterion 3.3.2 :
  • To be written

3.3.3 Changes Between Versions:

Changes to features that benefit accessibility since the previous user agent release are documented. @@Editors' Note: Link to the definition to benefit accessibility from previous 3.3.2 @@(Level AA)

• Intent of Success Criterion 3.3.3 :
  As accessibility features are implemented in new versions it is important for users to be able to be informed about these new features and how to operate them. The user should not have to discover which new features were implemented in the new version.
• Examples of Success Criterion 3.3.3 :
  • Sample text: "In this version, we added the ability to display tooltips on elements with a title attribute when using the keyboard. With caret browsing turned on simply arrowing onto an element with a title the tooltip will remain visible while the caret is within the element."
• Related Resources for Success Criterion 3.3.3 :
  • N/A

3.3.4 Centralized View:

There is a dedicated section of the documentation that presents a view of all features of the user agent necessary to meet the requirements of User Agent Accessibility Guidelines 2.0. (Level AAA)

• Intent of Success Criterion 3.3.4 :
  Specific accessibility features are important for users to know about and how to operate. The user should not have to discover where the accessibility features are documented in context (although that too is very useful). A specific section devoted to only accessibility features (e.g. keyboard shortcuts, how to zoom the viewport, where to find accessibility configuration settings), would make it easier for user to become more functional more quickly with the user agent.
• Examples of Success Criterion 3.3.4 :
  • A specific section in the documentation (local or online) detailing accessibility features of the user agent.[@@ Editor's Note: what about accessibility features of plugins, extensions, etc. they are not user agents by them selves. how do user find out about accessibility features if any in the extension?@@]
• Related Resources for Success Criterion 3.3.4 :
  • N/A

3.3.5 Context Sensitive Help:

There is context-sensitive help on all user agent features that benefit accessibility. (Level AAA)

• Intent of Success Criterion 3.3.5 :
  The purpose of this criteria is to help maximize the discovery of user agent features that benefit accessibility.
• Examples of Success Criterion 3.3.5 :
  • A user is exploring the menus of a user agent and finds a feature named Use My Style Sheet. Activating help the user quickly learns that this feature allows custom CSS stylesheets to be created to help make web content more accessible.
• Related Resources for Success Criterion 3.3.5 :
  • N/A

Implementing Guideline 3.4 - The user agent must behave in a predictable fashion. [Return to Guideline]

Summary: Moving the focus allows presentation of information (e.g. tooltips) but does not cause any other action (3.4.2). Users can prevent non-requested focus changes (3.4.1).

3.4.1 Avoid unpredictable focus [formerly 3.4.2, before that 5.4.2, and 1.9.10, broadened] :

The user can prevent focus changes that are not a result of explicit user request. (Level A)

• Intent of Success Criterion 3.4.1 :
  Users need to know that navigation in a web page is going to start in a predictable location and move in a predictable fashion. If a page moves the initial focus to somewhere other than the beginning of the page, the user may not realize they have skipped over some content, especially if they can only see a small portion of the page at a time. Similar problems may occur if the content or user agent automatically moves the focus while the user is reading or entering data on a page. If the focus moves without the user recognizing it, they can easily end up entering data in an incorrect field or taking other unintentional actions. Users can also become confused or disoriented when a window scrolls when they haven't requested it. This is particularly problematic for users who can only see a small portion of the document, and thus have to use more effort to determine their new context. Such users also are more likely to continue typing, not immediately realizing that the context has changed. Users for whom navigation is time consuming, tiring, or painful (including those using screen readers or with impaired dexterity) may also need more steps to return to the area where they want to work. While we recognize it may improve accessibility for some users on some pages to have the page to set focus to specific link or field when the page loads, it can also be detrimental for some users, and therefore users needs to be in control of this behavior.
• Examples of Success Criterion 3.4.1 :
  • Jerome has loaded a page that sets its default focus to a search box. Because he wants to read the content of the page, rather than starting by entering data, it takes him additional scrolling to get to the content that was not in the search box. To prevent this, he adjusts his browser's settings to disable the automatic focus change on this page.
  • Jessica uses a screen enlarger, and loads a page that contains instructions followed by a form. If the page automatically moves the keyboard focus to the form, she may not realize there were instructions. To avoid this problem, she sets an option to prevent default focus changes.
  • James uses speech recognition. He speaks his credit card number by saying several digits and, if needed, Tab keys, in a single phrase. He needs to know ahead of time whether it is necessary to include the Tab command in the phrase.
  • Joey is filling in a Web form that asks for his phone number using three separate fields. When she types the three digits of her area code into the first field, the browser automatically moves the focus to the second field. This can be a problem for two reasons, first because if Joey is not looking at the screen she does not realize that the focus has moved for her, and so she presses the Tab key to move it manually, not realizing that this now puts the focus on the third field rather than the the second. It can also pose a problem if Joey realizes that she typed one digit incorrectly in the area code field, because when she presses Shift+Tab to return and edit that field, the browser or content script checks the number of digits that have been entered, and seeing that it is three, automatically moves the focus once again, preventing her from editing the number. To avoid these problems, Joey goes to her browser's Preferences dialog box and checks the option that prevents focus changes that she has not explicitly requested.
  • Justine uses a keyboard macro to execute a multistep command at a specific location. The focus changes without her control, so the command fails or executes with unpredictable results.
• Related Resources for Success Criterion 3.4.1 :
  • UAAG 2.0 3.10.8 Don't Move Focus

3.4.2 Avoid Side Effects of Navigation [former 1.9.1, before that 3.11.11, changed]:

The user can move the keyboard focus without causing the user agent to take any further action, other than the presentation of information (e.g. scrolling or pop-ups that do not change the focus or selection). (Level A)

• Intent of Success Criterion 3.4.2 :
  People do not expect side effects when moving the keyboard focus. If users fail to notice side effects, they could end up doing something disastrous, and this is especially likely for users of assistive technology who cannot see changes happening elsewhere on the screen. Users may also find it confusing or disorienting if the effect causes unexpected focus movement or changes in context. If the user agent does implement side effects to keyboard navigation, it is recommended that it provide a user preference setting to disable them. However, in some cases it may be more appropriate to provide a separate navigation mechanism that avoids side effects, such as allowing the user to hold down the Ctrl key while navigating to avoid changing selection or choice.
  
  Note: It may not be possible for the user agent to detect or prevent side effects implemented by scripts in the content, but the user agent is required to prevent side effects that are under its control.
• Examples of Success Criterion 3.4.2 :
  • Murray uses a screen enlarger that allows him to see the element with the focus and a small area around it. He explores a dialog box by repeatedly pressing the Tab key to move to, and read, each control in succession, although he has to use the arrow keys to navigate between options in an option group. On this platform moving the focus to an option control automatically chooses that option, making it cumbersome for him because of the need to reset the choice to its original state afterward. Fortunately, the platform also has a convention that holding down the Ctrl key while navigating will move the focus without changing selection or option choice, so Murray uses this while exploring. His Web browser implements its own form controls and navigation mechanisms rather than using the platform's infrastructure, but it also implements this Ctrl-key mechanism for users like Murray.
• Related Resources for Success Criterion 3.4.2 :
  • UAAG 2.0 1.8.7 Don't Move Focus

@@ Editors' Note: Missing: Greater ease in interpreting security messaging. Should be cross-referenced with the security working group. @@

5.1.1 Non-Web-Based Accessible (Level A) :

Non-Web-based user agent user interfaces comply with and cite the requirements of standards or operating environment conventions that benefit accessibility. (Level A)

• Intent of Success Criterion 5.1.1:
  The user should be able to easily discover detailed information about the user agent's adherence to accessibility standards of the operating environment or adherence to external accessibility requirements without installing and testing the accessibility features.
• Examples of Success Criterion 5.1.1 :
  • User agent X lists the platform accessibility tools (high contrast, show sounds, sticky keys, etc) supported. Additionally, the user agent lists all of the platform accessibility APIs or other APIs that are supported. "User Agent X supports the Windows Accessibility API (MSAA) to display accessibility information and events for its features and web content."
• Related Resources for Success Criterion 5.1.1:
  • http://www.microsoft.com/windowsxp/using/accessibility/default.mspx
  • http://www.apple.com/accessibility/
  • http://www.linux.org/docs/ldp/howto/Accessibility-HOWTO/linuxos.html
  • http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2
  • http://developer.apple.com/ue/accessibility/
  • http://msdn.microsoft.com/en-us/library/dd373592%28VS.85%29.aspx
  • http://msdn.microsoft.com/en-us/windows/ee815673.aspx

5.2.1 Web-Based Accessible (Level A) :

User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level "A". (Level A)

5.2.2 Web-Based Accessible (Level AA) :

User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level "AA". (Level AA)

5.2.3 Web-Based Accessible (Level AAA) :

User agent user interfaces that are rendered using Web standard technologies conform to WCAG Level "AAA". (Level AAA)

• Intent of Guideline 5.2:
  Web-based applications which are intended to replace or enhance a desktop user agent or its functionality, but are in-fact built and rendered using standard Web technologies, are becoming increasingly common. These Web applications, windowless browsers, rich internet applications, HTML5 canvas, etc., perform similar functions to their desktop cousins and so must also conform to the accessibility requirements placed on a desktop user agent.
• Examples of Guideline 5.2:
  • Success criteria 2.7.1 requires that a user agent enable a user to change settings that impact accessibility. In this case we would expect that a Web-Based user agent should also enable a user to change accessibility settings specific to its functionality, which may in some cases enhance or override that of the platform on which it is executing: window-less browser, native operating system, etc.
• Related Resources for Guideline 5.2:
  • WAI-ARIA 1.0 User Agent Implementation Guide
  • W3C Web Design and Applications Activity

5.3.1 Implement accessibility features of content specs:

Implement and cite in the conformance claim the accessibility features of content specifications. Accessibility features are those that are either (Level A) :

• identified as such in the specification or
• allow authors to satisfy a requirement of WCAG.

• Intent of Success Criterion 5.3.1:
  
• @@ Editors' Note: add a sentence about the importance of content standards @@
  If browsers and players don't seamlessly conform to platform accessibility features, then users can't easily take advantage of those features. Software that has versions for different platforms, may have to handle accessibility differently on different platforms or operating systems. In order to show that you have implemented the accessibility features of the platform correctly, these features are identified in the conformance claim.
  
  The user should be able to easily discover detailed information about the user agent’s adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, and should be able to do so without installing and testing the accessibility features.
  
  
• Examples of Success Criterion 5.3.1 :
  • [@@ Editors' Note: We need an ARIA example here @@ ]
    In the conformance claim [link to conformance section], list the requirements you fully comply with, list the requirements you partially comply with and explain, and list the requirements you do not comply with and explain. Where applicable, this explanations can be general and cover several sections at once.
• Related Resources for Success Criterion 5.3.1:

  WCAG

  HTML

  CSS

  WAI-ARIA

5.3.2 Implement Accessibility Features of platform:

Implement and cite in the conformance claim the accessibility features of content and platform technology specifications. Accessibility features are those that are either (Level A) :

• identified as such in the specification or
• allow authors to satisfy a requirement of WCAG.

• Intent of Success Criterion 5.3.2:
  
• @@ Editors' Note: add a sentence about the importance of content standards @@
  If browsers and players don't seamlessly conform to platform accessibility features, then users can't easily take advantage of those features. Software that has versions for different platforms, may have to handle accessibility differently on different platforms or operating systems. In order to show that you have implemented the accessibility features of the platform correctly, these features are identified in the conformance claim.
  
  The user should be able to easily discover detailed information about the user agent's adherence to accessibility standards, including those related to content such as HTML and WAI-ARIA, platform standards such as MSAA or JAA, and third-party standards such as ISO 9241-171, and should be able to do so without installing and testing the accessibility features.
  
  
• Examples of Success Criterion 5.3.2 :
  • If you are developing for the Gnome platform, consult the Gnome Accessibility Developers Guide. For example, the Keyboard Focus section states: "Show current input focus clearly at all times. Remember that in controls that include a scrolling element, it is not always sufficient to highlight just the selected element inside that scrolling area, as it may not be visible. " If your program controls focus, make sure you conform to this accessibility guideline for focus.
    
    In the conformance claim [link to conformance section], list the requirements you fully comply with, list the requirements you partially comply with and explain, and list the requirements you do not comply with and explain. Where applicable, this explanations can be general and cover several sections at once.
• Related Resources for Success Criterion 5.3.2:

  [APPLE-ACCESS]

  "Introduction to Accessibility Overview," Apple Computer Inc.

  [CARBON-ACCESS]

  "Introduction to Accessibility Programming Guidelines for Carbon," Apple Corporation.

  [COCOA-ACCESS]

  "Introduction to Accessibility Programming Guidelines for Cocoa," Apple Corporation.

  [EITAAC]

  "EITAAC Desktop Software standards," Electronic Information Technology Access Advisory (EITAAC) Committee.

  [GNOME-ACCESS]

  "GNOME Accessibility for Developers," C. Benson, B. Cameron, B. Haneman, S. Snider, P. O'Briain, The GNOME Accessibility Project.

  [GNOME-API]

  "Gnome Accessibility Toolkit API"

  [GNOME-KDE-KEYS]

  "Gnome/KDE Keyboard Shortcuts," Novell Corporation.

  [IBM-ACCESS]

  "Software Accessibility," IBM Special Needs Systems.

  [IEC-4WD]

  IEC/4WD 61966-2-1: Colour Measurement and Management in Multimedia Systems and Equipment - Part 2.1: Default Colour Space - sRGB. May 5, 1998.

  [ISO-TS-16071]

  "Ergonomics of human-system interaction -- Guidance on accessibility for human-computer interfaces". International Organization for Standardization.

  [JAVA-ACCESS]

  "IBM Guidelines for Writing Accessible Applications Using 100% Pure Java," R. Schwerdtfeger, IBM Special Needs Systems.

  [JAVA-API]

  " Java Accessibility Package"

  [JAVA-CHECKLIST]

  "Java Accessibility Guidelines and Checklist," IBM Special Needs Systems.

  [MACOSX-KEYS]

  "Mac OS X keyboard shortcuts," Apple Corporation.

  [MS-ENABLE]

  "Accessibility for Applications Designers," Microsoft Corporation.

  [MS-WIN7-ACCESS]

  "Engineering Software For Accessibility", Microsoft Corporation.

  [MS-KEYS]

  "Keyboard shortcuts for Windows," Microsoft Corporation.

  [NOTES-ACCESS]

  "Lotus Notes application accessibility," IBM Corporation.

  [SUN-DESIGN]

  "Designing for Accessibility," Eric Bergman and Earl Johnson. This paper discusses specific disabilities including those related to hearing, vision, and cognitive function.

  [Editors' Note: Resource links from Jim - compare and expand]

  http://www.microsoft.com/windowsxp/using/accessibility/default.mspx

  http://www.apple.com/accessibility/

  http://www.linux.org/docs/ldp/howto/Accessibility-HOWTO/linuxos.html

  http://www.linuxfoundation.org/collaborate/workgroups/accessibility/iaccessible2

  http://developer.apple.com/ue/accessibility/

  http://msdn.microsoft.com/en-us/library/dd373592%28VS.85%29.aspx

  http://msdn.microsoft.com/en-us/windows/ee815673.aspx

5.4.1 Follow Specifications:

The user agent renders content according to the technology specification, except where it would actually harm overall accessibility. (Level A)

• Intent of Success Criterion 5.4.1:
  End users and assistive technology products assume that content will be rendered in a predictable fashion. This success criterion ensures that user agents provide this level of predictability. It may be necessary to ignore aspects of the technology specification where they would actually harm, rather than improve, overall accessibility. In these cases user agent developers are encouraged to deviate from those aspects of the standard, and document the decision in their conformance claim. For example, the CSS spec says generated content should not appear in the DOM, which may mean that generated content would not be exposed to assistive technology and thus may not be accessible to blind users. User agents should instead expose the generated content through the DOM, and document their decision to ignore that aspect of the specification.
• Examples of Success Criterion 5.4.1 :
  • A user agent implements the WAI-ARIA (Accessible Rich Internet Applications) standard, and the developer follows the "Implementing ARIA" document by mapping ARIA roles and events to the supported platform accessibility infrastructure (MSAA, UIA, ____, etc.). This allows a screen reader that supports the platform infrastructure to correctly support ARIA in the user agent.
  • An organization creates an optional style sheet that enlarges fonts and adapts all colors for maximum contrast. They can be confident that when their Web site uses this style sheet it will work with any browser because those browsers have implemented CSS according to the CSS specification.
• Related Resources for Success Criterion 5.4.1:
  • Guideline 5.3

5.4.2 Handle Unrendered Technologies:

If the user agent does not render a technology, the user can choose a way to handle content in that technology (e.g. by launching another application or by saving it to disk). (Level A)

• Intent of Success Criterion 5.4.2:
  Users who have disabilities may have fewer options in terms of how they access the information. Information is made available in a variety of ways on the Internet, and at times a specific format may be the only way in which information is available. If the user agent cannot render that format it should let the user access that content through alternate means, such as invoking a third-party renderer or saving the file to the user's hard drive.
• Examples of Success Criterion 5.4.2 :
  • Tracy has low vision and finds it much more convenient to access her bank statement electronically than on paper, even though the electronic version is in a TIFF image, a format that her browser cannot render. In this case, the browser lets her save the image to her hard drive so she can open it in another program.
• Related Resources for Success Criterion 5.4.2
  • To be written

5.4.3 Alternative content handlers:

The user can select content elements and have them rendered in alternative viewers. (Level AA)

• Intent of Success Criterion 5.4.3:
  When accessing media content on the Web, users with disabilities sometimes find they have a richer or more accessible experience in a third-party application than using the browser's built-in facilities. In these cases they want to be able to navigate to content in their browser, then save that content to their disk or launch it in a third-party application.
• Examples of Success Criterion 5.4.3 :
  • A browser supports the VIDEO tag and adds its own play and pause controls, but George prefers to view the video content in a third-party application that provides much more sophisticated navigation controls such as bookmarks, skip-forward and backwards, and the ability to speed playback without increasing pitch of the audio track. In the browser, he right-clicks on the video to display a context menu, and from that chooses "Open in…", and then chooses his preferred video player. The browser launches the player to show that video file in the browser's cache folder. The browser saves the video to a temporary location on the user's disks (or uses one already in its cache folder), then launches the player to show that file.
    
    In the case of streaming video that cannot be saved to disk, the browser launches the external viewer, passing it the URL to the online video.
• Related Resources for Success Criterion 5.4.3
  • To be written